Use example of _ name _ in Python, and python _ name _

Use example of _ name _ in Python, and python _ name _

1. If the module is imported, the value of __name _ is the module name.
2. If the module is directly executed, the value of __name _ is '_ main __'

Py1.py
Copy codeThe Code is as follows:
#! /Usr/bin/env python
Def test ():
Print '_ name _ =' ,__ name __
If _ name _ = '_ main __':
Test ()

Py2.py
Copy codeThe Code is as follows:
#! /Usr/bin/env python
Import Py1.py
 
Def test ():
Print '_ name _ =' ,__ name __
If _ name _ = '_ main __':
Test ()
Print 'py1. py _ name _ = ', Py1. _ name __

Execution result:
Copy codeThe Code is as follows:
_ Name __=__ main __
Py1.py _ name __= Py1

The result shows that Py2.py is directly executed, and the value of the built-in Variable _ name _ is _ main __; otherwise, it is the module name, with this feature, you can add test code in the if statement to reduce bugs and improve program robustness.
Copy codeThe Code is as follows:
If _ name _ = '_ main __':
Test ()